We move on now to the new developments near St. Louis, Missouri this evening after the police shooting of an unarmed teenager. Police using tear gas for a third night in a row overnight. This demonstrator throwing a canister back. Tensions have been high all week long, a community demanding answers. This evening, what they are revealing about the officer in that car. His condition. ABC Steve osunsami is there tonight. Reporter: Late this evening the protests continue down the streets of Ferguson. They are demanding answers in the police shooting of an unarmed teenager at the center of this movement. The city is torn. The police chief scheduled to meet with the victim's family tomorrow. With death threats coming in daily, police refuse to identify the officer, who gunned down 18-year-old Michael brown, just two days before he should have started college. If it comes down to a lawsuit, police promise to appeal the issue to the highest court. They argue there was a fight at the scene. Today told us the officer was injured in the scuffle and had to be treated at a hospital. His face was swollen, he obviously had been hit or punched or something like that. Reporter: Tear gas has been filling the air, and bullets are lighting up the night, even shooting at police helicopters, the FAA so concerned they issued a no fly zone covering the entire city. Today, we met Brandon lee, student and photographer, who says the young people clashing with police aren't thugs. That this is civil disobedience. He asked us to show these pictures of people cleaning the streets. I understand where the brothers are coming from doing the looting and robbing, this country, come on, just look on the news. No jobs. All of us in prison. Reporter: To prevent this, the city is asking people who live here to March and protest during daylight hours. But families here tell us, they should be able to demonstrate whenever they would like.

This transcript has been automatically generated and may not be 100% accurate.

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